The present invention relates to an electromagnetic valve, in particular a pressure regulating valve for automatic transmissions of motor vehicles.
Electromagnetic valves of the above mentioned general type are known in the art. One of such electromagnetic valves is disclosed for example in the German document DE-GM 82 20 790. The electromagnetic valve disclosed in this document has a magnet housing with a valve closing element mounted on it. The valve closing element serves on the one hand for hydraulic connection at the place of mounting and on the other hand has a longitudinal opening of a valve slider which has control portions cooperating with control edges of the valve closing element. The valve closing element such as an electromagnetic valve is a rotary part produced in a material removing process, and the material as a rule is aluminum. The material removal expense is very high for this, and the machining during the manufacture is expensive and complicated. In particular the production of the control edges is complicated and expensive since as a rule they are formed as control grooves which surround the longitudinal opening. The rotary tool for producing the control grooves is inserted the longitudinal opening and moved. To the smooth side of the conventional pressure regulating valves the tool required for this work is prone to vibrations and breakage. Moreover, during the machining of the valve closing element a lot of particles and chips are produced, which must be subsequently mechanically removed. During the formation of the ring grooves and control edges on the longitudinal opening of the valve closing element it is necessary as a rule to clamp the workpiece around since a machining of the control grooves from only one side can lead to unfavorably long rotary tools.